The Berlin-based builder of e-commerce startups shrank first-quarter losses at some key startups by 40 million euros ($45 million) while its HelloFresh and Westwing businesses struggled in Germany, according to a statement from the company Tuesday.

Analysts balked at tepid growth at some European holdings and the absence of profit numbers for Delivery Hero, a food business in Germany, complicating the valuation of that asset. Rocket is under pressure to prove it is backing the right startups as many of them had showed showed little progress reducing losses last year.

"These selected details are very selective indeed and we would suggest are not quite of the magnitude of ’significant progress made on their path to profitability’," Neil Campling, an analyst at Northern Trust Securities, said in a note to clients. "The statement has to be taken with a huge grain of salt.”

Rocket’s stock has fallen 25% this year.

Results at Rocket, founded by German entrepreneur Oliver Samwer and his brothers and taken public in 2014, are seen as a key barometer of whether Germany’s buoyant startup scene can produce listed companies with longevity.

Sales grew by an average of 34% at selected startups in the first quarter while the companies reduced their adjusted losses by 23% on average compared with a year earlier.

Revenue in Rocket’s food, fashion, general merchandise, and home furnishings divisions were 532 million euros in the first quarter, not counting its one-time stake in Asian online retailer Lazada, sold to China’s Alibaba in April. Lazada is No. 159 in the Internet Retailer 2016 Asia 500. Adjusted operating margin improved by 16 percentage points to negative 22% during the quarter. Companies including Global Fashion Group helped boost sales.

"We are going in the right direction on our path to profitability," CEO Samwer said on a call with reporters.

Other startups in Rocket’s stable posted poorer performance. African e-retailer Jumia’s sales fell from a year ago, and food-ordering site HelloFresh widened its loss to 27.3 million euros from 7.3 million euros a year earlier, on an adjusted basis. In Latin America, Linio’s sales fell to 9.8 million euros from 20 million euros a year earlier. Samwer said Rocket hasn’t decided whether to attempt a turnaround or exit the investment.

Reduced valuations

Rocket is trying to convince investors that the holding company, which controls dozens of startups in Europe, Russia, Latin America and Africa, can succeed in its strategy to sell in markets outside the U.S. and China. That’s in doubt following operating losses last year and pared valuations at some of its holdings.

Many of its companies were still in the growth phase and needed investments in 2015, Samwer said earlier this year, vowing to show "significant" improvements in profitability this year and next.

Christoph Sandner, an analyst at MainFirst Bank in Frankfurt, said in a note that slow revenue growth at Home24 and Westwing show difficulties in the furnishings business and HelloFresh’s losses raise doubts about how much revenue would have grown there without heavy marketing expenses. He has an outperform rating on Rocket.

CEO Samwer reiterated his previous guidance that three of Rocket’s so-called "proven winner" companies would be profitable by the fourth quarter of next year.

Investment AB Kinnevik, the second-biggest shareholder in Rocket, will evaluate its stake once the holdings will mature in two to three years, CEO Lorenzo Grabau told Swedish newspaper Dagens Nyheter earlier this month. The Samwers still are the biggest shareholder in Rocket.